<?php
class Inchoo_Cpa_Block_Cat_New_Form extends Mage_Adminhtml_Block_Widget_Form
{
  protected function _prepareForm()
  {
      $form = new Varien_Data_Form(array('id' => 'edit_form', 'action' => $this->getData('action'), 'method' => 'post'));
      $form->setUseContainer(true);
      $this->setForm($form);
      return parent::_prepareForm();
  }
}